Merge branch 'cc/replace-object-info'

read_sha1_file() that is the workhorse to read the contents given
an object name honoured object replacements, but there is no
corresponding mechanism to sha1_object_info() that is used to
obtain the metainfo (e.g. type & size) about the object, leading
callers to weird inconsistencies.

* cc/replace-object-info:
  replace info: rename 'full' to 'long' and clarify in-code symbols
  Documentation/git-replace: describe --format option
  builtin/replace: unset read_replace_refs
  t6050: add tests for listing with --format
  builtin/replace: teach listing using short, medium or full formats
  sha1_file: perform object replacement in sha1_object_info_extended()
  t6050: show that git cat-file --batch fails with replace objects
  sha1_object_info_extended(): add an "unsigned flags" parameter
  sha1_file.c: add lookup_replace_object_extended() to pass flags
  replace_object: don't check read_replace_refs twice
  rename READ_SHA1_FILE_REPLACE flag to LOOKUP_REPLACE_OBJECT

8 files changed, 141 insertions, 26 deletions

diff --git a/Documentation/git-replace.txt b/Documentation/git-replace.txt
index f373ab48d4..0a02f70657 100644
--- a/Documentation/git-replace.txt
+++ b/Documentation/git-replace.txt
@@ -10,7 +10,7 @@ SYNOPSIS
 [verse]
 'git replace' [-f] <object> <replacement>
 'git replace' -d <object>...
-'git replace' -l [<pattern>]
+'git replace' [--format=<format>] [-l [<pattern>]]
 
 DESCRIPTION
 -----------
@@ -70,6 +70,23 @@ OPTIONS
 	Typing "git replace" without arguments, also lists all replace
 	refs.
 
+--format=<format>::
+	When listing, use the specified <format>, which can be one of
+	'short', 'medium' and 'long'. When omitted, the format
+	defaults to 'short'.
+
+FORMATS
+-------
+
+The following format are available:
+
+* 'short':
+	<replaced sha1>
+* 'medium':
+	<replaced sha1> -> <replacement sha1>
+* 'long':
+	<replaced sha1> (<replaced type>) -> <replacement sha1> (<replacement type>)
+
 CREATING REPLACEMENT OBJECTS
 ----------------------------
 
diff --git a/builtin/cat-file.c b/builtin/cat-file.c
index f8288c830c..f12071adc4 100644
--- a/builtin/cat-file.c
+++ b/builtin/cat-file.c
@@ -241,7 +241,7 @@ static int batch_one_object(const char *obj_name, struct batch_options *opt,
 		return 0;
 	}
 
-	if (sha1_object_info_extended(data->sha1, &data->info) < 0) {
+	if (sha1_object_info_extended(data->sha1, &data->info, LOOKUP_REPLACE_OBJECT) < 0) {
 		printf("%s missing\n", obj_name);
 		fflush(stdout);
 		return 0;
diff --git a/builtin/replace.c b/builtin/replace.c
index b1bd3ef994..2336325ce3 100644
--- a/builtin/replace.c
+++ b/builtin/replace.c
@@ -16,27 +16,69 @@
 static const char * const git_replace_usage[] = {
 	N_("git replace [-f] <object> <replacement>"),
 	N_("git replace -d <object>..."),
-	N_("git replace -l [<pattern>]"),
+	N_("git replace [--format=<format>] [-l [<pattern>]]"),
 	NULL
 };
 
+enum replace_format {
+      REPLACE_FORMAT_SHORT,
+      REPLACE_FORMAT_MEDIUM,
+      REPLACE_FORMAT_LONG
+};
+
+struct show_data {
+	const char *pattern;
+	enum replace_format format;
+};
+
 static int show_reference(const char *refname, const unsigned char *sha1,
 			  int flag, void *cb_data)
 {
-	const char *pattern = cb_data;
+	struct show_data *data = cb_data;
 
-	if (!fnmatch(pattern, refname, 0))
-		printf("%s\n", refname);
+	if (!fnmatch(data->pattern, refname, 0)) {
+		if (data->format == REPLACE_FORMAT_SHORT)
+			printf("%s\n", refname);
+		else if (data->format == REPLACE_FORMAT_MEDIUM)
+			printf("%s -> %s\n", refname, sha1_to_hex(sha1));
+		else { /* data->format == REPLACE_FORMAT_LONG */
+			unsigned char object[20];
+			enum object_type obj_type, repl_type;
+
+			if (get_sha1(refname, object))
+				return error("Failed to resolve '%s' as a valid ref.", refname);
+
+			obj_type = sha1_object_info(object, NULL);
+			repl_type = sha1_object_info(sha1, NULL);
+
+			printf("%s (%s) -> %s (%s)\n", refname, typename(obj_type),
+			       sha1_to_hex(sha1), typename(repl_type));
+		}
+	}
 
 	return 0;
 }
 
-static int list_replace_refs(const char *pattern)
+static int list_replace_refs(const char *pattern, const char *format)
 {
+	struct show_data data;
+
 	if (pattern == NULL)
 		pattern = "*";
+	data.pattern = pattern;
 
-	for_each_replace_ref(show_reference, (void *) pattern);
+	if (format == NULL || *format == '\0' || !strcmp(format, "short"))
+		data.format = REPLACE_FORMAT_SHORT;
+	else if (!strcmp(format, "medium"))
+		data.format = REPLACE_FORMAT_MEDIUM;
+	else if (!strcmp(format, "long"))
+		data.format = REPLACE_FORMAT_LONG;
+	else
+		die("invalid replace format '%s'\n"
+		    "valid formats are 'short', 'medium' and 'long'\n",
+		    format);
+
+	for_each_replace_ref(show_reference, (void *) &data);
 
 	return 0;
 }
@@ -127,19 +169,27 @@ static int replace_object(const char *object_ref, const char *replace_ref,
 int cmd_replace(int argc, const char **argv, const char *prefix)
 {
 	int list = 0, delete = 0, force = 0;
+	const char *format = NULL;
 	struct option options[] = {
 		OPT_BOOL('l', "list", &list, N_("list replace refs")),
 		OPT_BOOL('d', "delete", &delete, N_("delete replace refs")),
 		OPT_BOOL('f', "force", &force, N_("replace the ref if it exists")),
+		OPT_STRING(0, "format", &format, N_("format"), N_("use this format")),
 		OPT_END()
 	};
 
+	read_replace_refs = 0;
+
 	argc = parse_options(argc, argv, prefix, options, git_replace_usage, 0);
 
 	if (list && delete)
 		usage_msg_opt("-l and -d cannot be used together",
 			      git_replace_usage, options);
 
+	if (format && delete)
+		usage_msg_opt("--format and -d cannot be used together",
+			      git_replace_usage, options);
+
 	if (force && (list || delete))
 		usage_msg_opt("-f cannot be used with -d or -l",
 			      git_replace_usage, options);
@@ -157,6 +207,9 @@ int cmd_replace(int argc, const char **argv, const char *prefix)
 		if (argc != 2)
 			usage_msg_opt("bad number of arguments",
 				      git_replace_usage, options);
+		if (format)
+			usage_msg_opt("--format cannot be used when not listing",
+				      git_replace_usage, options);
 		return replace_object(argv[0], argv[1], force);
 	}
 
@@ -168,5 +221,5 @@ int cmd_replace(int argc, const char **argv, const char *prefix)
 		usage_msg_opt("-f needs some arguments",
 			      git_replace_usage, options);
 
-	return list_replace_refs(argv[0]);
+	return list_replace_refs(argv[0], format);
 }
diff --git a/cache.h b/cache.h
index ce377e1354..9ba9773edf 100644
--- a/cache.h
+++ b/cache.h
@@ -760,11 +760,11 @@ int daemon_avoid_alias(const char *path);
 int offset_1st_component(const char *path);
 
 /* object replacement */
-#define READ_SHA1_FILE_REPLACE 1
+#define LOOKUP_REPLACE_OBJECT 1
 extern void *read_sha1_file_extended(const unsigned char *sha1, enum object_type *type, unsigned long *size, unsigned flag);
 static inline void *read_sha1_file(const unsigned char *sha1, enum object_type *type, unsigned long *size)
 {
-	return read_sha1_file_extended(sha1, type, size, READ_SHA1_FILE_REPLACE);
+	return read_sha1_file_extended(sha1, type, size, LOOKUP_REPLACE_OBJECT);
 }
 extern const unsigned char *do_lookup_replace_object(const unsigned char *sha1);
 static inline const unsigned char *lookup_replace_object(const unsigned char *sha1)
@@ -773,6 +773,12 @@ static inline const unsigned char *lookup_replace_object(const unsigned char *sh
 		return sha1;
 	return do_lookup_replace_object(sha1);
 }
+static inline const unsigned char *lookup_replace_object_extended(const unsigned char *sha1, unsigned flag)
+{
+	if (!(flag & LOOKUP_REPLACE_OBJECT))
+		return sha1;
+	return lookup_replace_object(sha1);
+}
 
 /* Read and unpack a sha1 file into memory, write memory to a sha1 file */
 extern int sha1_object_info(const unsigned char *, unsigned long *);
@@ -1098,7 +1104,7 @@ struct object_info {
 		} packed;
 	} u;
 };
-extern int sha1_object_info_extended(const unsigned char *, struct object_info *);
+extern int sha1_object_info_extended(const unsigned char *, struct object_info *, unsigned flags);
 
 /* Dumb servers support */
 extern int update_server_info(int);
diff --git a/replace_object.c b/replace_object.c
index d0b1548726..cdcaf8cbe2 100644
--- a/replace_object.c
+++ b/replace_object.c
@@ -97,9 +97,6 @@ const unsigned char *do_lookup_replace_object(const unsigned char *sha1)
 	int pos, depth = MAXREPLACEDEPTH;
 	const unsigned char *cur = sha1;
 
-	if (!read_replace_refs)
-		return sha1;
-
 	prepare_replace_object();
 
 	/* Try to recursively replace the object */
diff --git a/sha1_file.c b/sha1_file.c
index daacc0cfb0..ee224e4128 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -2443,13 +2443,14 @@ static int sha1_loose_object_info(const unsigned char *sha1,
 	return 0;
 }
 
-int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi)
+int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi, unsigned flags)
 {
 	struct cached_object *co;
 	struct pack_entry e;
 	int rtype;
+	const unsigned char *real = lookup_replace_object_extended(sha1, flags);
 
-	co = find_cached_object(sha1);
+	co = find_cached_object(real);
 	if (co) {
 		if (oi->typep)
 			*(oi->typep) = co->type;
@@ -2461,23 +2462,23 @@ int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi)
 		return 0;
 	}
 
-	if (!find_pack_entry(sha1, &e)) {
+	if (!find_pack_entry(real, &e)) {
 		/* Most likely it's a loose object. */
-		if (!sha1_loose_object_info(sha1, oi)) {
+		if (!sha1_loose_object_info(real, oi)) {
 			oi->whence = OI_LOOSE;
 			return 0;
 		}
 
 		/* Not a loose object; someone else may have just packed it. */
 		reprepare_packed_git();
-		if (!find_pack_entry(sha1, &e))
+		if (!find_pack_entry(real, &e))
 			return -1;
 	}
 
 	rtype = packed_object_info(e.p, e.offset, oi);
 	if (rtype < 0) {
-		mark_bad_packed_object(e.p, sha1);
-		return sha1_object_info_extended(sha1, oi);
+		mark_bad_packed_object(e.p, real);
+		return sha1_object_info_extended(real, oi, 0);
 	} else if (in_delta_base_cache(e.p, e.offset)) {
 		oi->whence = OI_DBCACHED;
 	} else {
@@ -2499,7 +2500,7 @@ int sha1_object_info(const unsigned char *sha1, unsigned long *sizep)
 
 	oi.typep = &type;
 	oi.sizep = sizep;
-	if (sha1_object_info_extended(sha1, &oi) < 0)
+	if (sha1_object_info_extended(sha1, &oi, LOOKUP_REPLACE_OBJECT) < 0)
 		return -1;
 	return type;
 }
@@ -2591,8 +2592,7 @@ void *read_sha1_file_extended(const unsigned char *sha1,
 	void *data;
 	char *path;
 	const struct packed_git *p;
-	const unsigned char *repl = (flag & READ_SHA1_FILE_REPLACE)
-		? lookup_replace_object(sha1) : sha1;
+	const unsigned char *repl = lookup_replace_object_extended(sha1, flag);
 
 	errno = 0;
 	data = read_object(repl, type, size);
diff --git a/streaming.c b/streaming.c
index debe904523..9659f18be2 100644
--- a/streaming.c
+++ b/streaming.c
@@ -113,7 +113,7 @@ static enum input_source istream_source(const unsigned char *sha1,
 
 	oi->typep = type;
 	oi->sizep = &size;
-	status = sha1_object_info_extended(sha1, oi);
+	status = sha1_object_info_extended(sha1, oi, 0);
 	if (status < 0)
 		return stream_error;
 
diff --git a/t/t6050-replace.sh b/t/t6050-replace.sh
index 7d47984352..719a11673b 100755
--- a/t/t6050-replace.sh
+++ b/t/t6050-replace.sh
@@ -276,6 +276,48 @@ test_expect_success '-f option bypasses the type check' '
 	git replace -f HEAD^ $BLOB
 '
 
+test_expect_success 'git cat-file --batch works on replace objects' '
+	git replace | grep $PARA3 &&
+	echo $PARA3 | git cat-file --batch
+'
+
+test_expect_success 'test --format bogus' '
+	test_must_fail git replace --format bogus >/dev/null 2>&1
+'
+
+test_expect_success 'test --format short' '
+	git replace --format=short >actual &&
+	git replace >expected &&
+	test_cmp expected actual
+'
+
+test_expect_success 'test --format medium' '
+	H1=$(git --no-replace-objects rev-parse HEAD~1) &&
+	HT=$(git --no-replace-objects rev-parse HEAD^{tree}) &&
+	MYTAG=$(git --no-replace-objects rev-parse mytag) &&
+	{
+		echo "$H1 -> $BLOB" &&
+		echo "$BLOB -> $REPLACED" &&
+		echo "$HT -> $H1" &&
+		echo "$PARA3 -> $S" &&
+		echo "$MYTAG -> $HASH1"
+	} | sort >expected &&
+	git replace -l --format medium | sort > actual &&
+	test_cmp expected actual
+'
+
+test_expect_success 'test --format long' '
+	{
+		echo "$H1 (commit) -> $BLOB (blob)" &&
+		echo "$BLOB (blob) -> $REPLACED (blob)" &&
+		echo "$HT (tree) -> $H1 (commit)" &&
+		echo "$PARA3 (commit) -> $S (commit)" &&
+		echo "$MYTAG (tag) -> $HASH1 (commit)"
+	} | sort >expected &&
+	git replace --format=long | sort > actual &&
+	test_cmp expected actual
+'
+
 test_expect_success 'replace ref cleanup' '
 	test -n "$(git replace)" &&
 	git replace -d $(git replace) &&